Max Length of Supply/Return Legs for Panel Rads - Two Pipe Reverse Return

NTL1991

Hey guy, I've been reading Dan's books on Pumping Away, and Primary Secondary Piping. I'm curious if there are any rules-of-thumb about how long supply and return legs for a panel rad can be coming off 2-pipe reverse return mains.

If a 2-pipe reverse return main was looped around the basement, would it be possible to shoot each radiator's supply and return legs two, possibly three floors up? I'd imagine filling and bleeding a system like this would be a challenge?

hot_rod

panel rads typically have bleeders, so purging should not be a problem. Not much different then a radiant manifold mounted in the basement.